Wilhelm penzold



W. PENZOLD ELECTRICAL HEATING APPARATUS May 13) 1924.

Filed April 18. 192s .d M@ w@ e f W d n 4. m F

Patented May 13, 1924.

UNITED STATES PATENT OFFICE.

WILHELM PENzoLD, or HANcvEn, GERMANY, Assrenca To wrnnnsrann AKTIEN GESELLSCHAFT FR ELEKTROMEME-TECHNIK, or HANOVER, GER-MANY.

ELECTRICAL HEATING APPARATUS.

Application filed April 18, 1923.

T 0 all w hom it may wacom.'

Be it known that I, VrLi-IELM PENZOLD, a citizen of Germany. residing at Hanover, in the State ot Prussia, Germany, have invented certain new and useful Improvements in Electrical Heating Apparatus; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in electrical heating apparatus, and more particularly in apparatus for electrically heating liquids providing the electrical resistance for transforming the electrical energy into heat.. In apparatus of this type the field of the use of concentrically arranged electrodes is limited, because it is dititicult to produce the high resistance required in connection with high pressure currents7 the reason residing in the unfavorable field distribution of a concentric arrangement.

The object of the improvements is to provide an apparatus in which, with the same surface area of the immersed electrodes, any desired resistance between the infinite value and a minimum can be produced. With this object in view I provide insulating rings between the electrodes the relative distance of which can be varied from zero to a certain value.

In order that my invention be more clearly understood several examples embodying the same have been shown in the accompanying drawing in which the same reference characters have been used in all the views to indicate corresponding parts.

In said drawing,

Fig. 1, is a vertical section showing the insulating rings placed in close contact one above the other,

Fig. 2, is a similar section showing the said rings spaced from one another,

Fig. 3, is a plan view of Fig. l,

Fig. 4, is a section taken on the line 4 4 of Fig. 5 and showing a modified form of the insulating rings,

Fig. 5, is a section taken on the line 5-5 of Fig. 4, and

Fig. 6, is a plan view showing a modifi cation suitable for operation by three-phase alternating current.

Serial N0. 632,883.

In the example shown in Figs. l to 3 my improved heating apparatus consists of a receptacle d of cylindrical form having an electrode a passed through its top and insulated therefrom and carrying at its bottom end a disk c of insulating material.

vThe said electrode is surrounded by disks b of insulating material which in the position shown kin Fig. l are placed in contact one above the other, so that there is no electrical connection through the body of the liquid from the inner electrode a to the outer electrode provided by the wall of the receptacle or boiler cl. By elevating the insulating rings b so that the consecutive rings are spaced apart and some of them are disposed above the level of the liquid, as is shown in Fig. 2, annular passages are formed between the rings and in the body ot the liquid, and the total cross-sectional area of the said passages is chosen according to the desired electrical etl'ect. Means for thus elevating the rings will readily suggest themselves to those skilled in the art, and I deem it not necessary to describe a construction. By the insulating disk c a shunt circuit from the bottom end of the inner electrode u. to the wall of the boiler is avoided, and the current flows in radial direction from the inner electrode a to the wall of the boiler. To permit upward movement of the hot liquid and the bubbles of steam the insulating bodies are preferably formed with bores f tapering outwardly at their bottom ends to facilitate upward movement of the steam bubbles.

In the modiiication shown in Figs. 4 and 5 the insulating rings g are provided at their top sides with spacing lugs e provided in lieu of the elevating means described with reference to Figs. l to 3.

Fig. 6 shows a modification suitable for operation by threephase alternating current.

I claim:

1. An electrical heating apparatus, comprising a receptacle for the liquid to be heated, an inner electrode, and spaced insulating rings surrounding the inner elec` trode.

2. An electrical heating apparatus, comprising a receptacle for the liquid to be heated, an inner electrode, and spaced insulating rings surrounding the inner electrode and foraminated for permitting the passage oi' liquid and vapor.

3. An electrical heating apparatus, oomprising a receptacle for the liquid to be heated, an inner electrode, and spaced insu` lating rings surrounding the inner electrode and formed With openings tapering out- Wardly at their bottom ends and permit- 

